Breech mechanism for guns



April 1929- G. M. McCANN 1,707,444

BREECH MECHANISM FOR GUNS Filed Jan. 15, 1926 2 Sheets-Sheet 1 k 22 gnue'ntoz EE E'E I"I-M Ban-m MWWZ April 2, 1929. G. M. MVCCANN 1,707,444

BREECH MECHANISM FOR GUNS zlvwento'o 'Eetlrge M-M EET'LTL MWWX Patented Apr. 2, 1929.

Tihejiinventionzdescribed herein vmay; be"

i the, payInenti-tdme of any. royalty thereon. 5v anismifon'guns;

toithelchamberl important considera 5 ammunifinnseqnipped-i with a-sensitive nose fusenuflihis facility in. loading may be affonded by thezuse oiiia vertical or drop-breech block whereinithe upper part of the breech Yringzisacutawayr However, a drop-breech blockiisinot-suitahle to high angle firing by. "reason'oftclearanceswhich would have to be provided: and inherently because of the,

' .to thei closed; position: 7 V

2 f;: Ehei..pr1nc1palobjectof this invention is '1' all theadvantages-ofi the drop block with. the simplioityiofthe sliding block.

-'?A J 1 othen important object is to provide; a. latch mechanism which prevents the breech;

-" loader'andiwhichis conveniently." positioned; to be' tripped' by the loader as his hand is; yvmithdraw nza fterrammingg home the round. Aimovd Lcatchdsprovided with is adapted to- *l'lbld'thQlfitChzill bOththe raisediand lowered:

rpo'sitioni' tIiabloek: ap-ivotedtray which is positioned isropeni;

' ;5'llo;-'theseand otherends, my invention coiisistssinktheE construction, arrangement; ik idbombinationof elements, described here-' ,nglza pant'ofzthis specification.

A practical embodimentiof the invention.

wherein:" j g g I i. fflEigs :1 isk a fragmentary plan view. of a g unprovidedzwith a'breech mechanismconstnnctediinsaocordance with. the invention;

vmilinui'fac'tured1andeusedbyor for the Govermnent;fongovennmental purposes without vThiss' invention; relates. to a breech mech- Iirfiring: a: gun ,at high elevations. the opi- 1' enatziomof inserting the round of iammuntion' inteithe chainber is greatly facilitated; when 0 loader has a; clear-view of the entrance tionwhiohqdictates I the provision of such a" in aibreechzmechanism is the ele-v s' ment .of ;.saietyr.obtained when handling,

? addedfniechanism:requiredato raise the block 1 tori providaza breech .mechanism. combining t blocki firom being; closedron the handi of. the" Astill' furtherobject is toassociate with- '40 tb supportilthe. roundnwhen the breechblock 4,5 inafter;jandipointed out inthe [claims formise'illustrated' inwtheaccompanying drawings,

BREEGHYMEQHANISM For. Guns. 7 m lication meep'ranuaryis, 1926. Serial No.- 81,549.- 1

1 (GRANTED UNDER THE ACT OFIMARCHT3, 1883, is AMENDED1APRIL"30,*1928"; 370' o.= c. 757.

-Fig. 2 is a; view inright si'de -elevation thereof;-

Fig. 3 is as View. in rear elevation and partly in section with the breech block openz and the latch in positionpnior to inserting;

the round; Y

Fig. 4 is a similar: view showing therelation between the latch and? the block' at the hon'ie'and theilatchflraisedg.

. Fig, 5. 's a sectional view through the:

'cEoRs'E M. MCFCANVN, orilvnw' CASTLE, nntawaitn; a 7

00 moment when the round has been rammed;

breech ring taken on the line 55 of Fig: 1'":

and showing the the block closed;:

Fig. 6 is the latch; I Fig. 7 is a View inside Fig. 8-is a detail positiona of: the latch with elevation :thereo-f; view-inislde "elevatlon of the; latch catch Fig. 9 is an end view thereofland' 'Figs. 10 and 11 are detail views-of the breech block tray. Y I

Referring to the drawings by numerals of reference:

i V The breechming 5 o'iia gun-istransversely recessed to-receive a sliding b'reech block 6 which is manually: movedto its open and closed position by -mean's of an operating lever 7 pivoted in the breech ring and hav ing a cross headi8 work ingsin aicam groove- 9 in the-upper faceoflthe blocka; Pivot'ed to" the blockis a tray 10 having-'apin' 1-12 riding in agroove 12: in the breech" ring: during reciprocationofthe blockg" When the block is open, the tray: is idroppedgi as shown in Figures 3 and 4;.so as to provide'ia rest for a detail View inr'ear elevation o V i theshell at it is being inSerted in tIie cham her; When the block is fcl'osed the tray' is folded against the end iof theblock, as shown in Figure 5 so as" not to project beyond the breech ring. a

The breech ring is also provide d with the usual circular loading aperture 13 -to 'per mit insertion: of; the: round and; as in the typical drop block breech: mechanism, theportion of the" breech ringiaboVe this apere ture is cut away to providean opening 14v 1 so that a clear view of 'the mouth of the chamber is afforded when the g 3ju'n -'i'sin? highelevation and also to permit -the lbaden to. carry hishand thro'ughto'clear the-pieceafter ramming in a round.-

4O Lone ofitsribs 1 6 isadapted to contact the 1.1 confined between the breech ring and a .foot 18:0n the :latch whileia finger grip 19 is This arrangement is utilized 'to conveniently position a suitable latch mechanism which normally; preventst-he breech. block frombeing close'd on. the hand of theloader and which may be tripped by the loader with perfect safety an d Without special. ef-

of the breech block by means of a spring 17 provided. on the upper end of the latch e eby it may be raised.

'Mountedinthe breech ring tothe; left of 1:": the latch is a spring'pressed catch 20 whose end 21;is adapted to engage in arecess15 in the latch (Fig. to hold the sameclear' of they-block after it has been manually raised.1*

A s thebreech-block is moved in: closing" a depending lug 22 on the catch enters. a groove 23 in; the upper face ofthe block and final movement :of the block serves to with .is brought up against the end of the groove.-

before the block arrives home, so that .the

' draw the catch from the recess 15v in-the latch (F ig. 5) thereby permitting therla'tch' to be depressed sufiiciently by its spring to prevent reentry of the catch in the recess 15'.. "The latch in this :position rests. upon the block and is subsequently enabled to as sume its lower-wost position when the block is open asseen in Figure' 3. In order to limit the downward movement-of the latch,

catch.

or; less conventional extractor 24L; operating in a well known manner and whose-upper hub 25 is'disposed in a cam 'groove26 in the bottom of the block. As the round is -inserted into the chamber its flange engages thelip 27 0f the extractor and results in .moving the block sufficiently :to the vleft to prevent the round from falling outof the chamber.

The movement of the'block is limited by the latch and is in the position shown in Figure 4. Movement of the block to closed" position can not be completed unless the latch has been' lifted byfth loader.

- In all operations of thebreechimechanism thereis no'danger'of the hand otithe loader I being struck by the block ashis-hand will be vWhile in theiforegoing there has been clear of the block when raising the latch -ill ustrated and described such combination 1 and arrangement. of elements .asiconstitut'e the preferred embodiment of my invention, 1t is nevertheless .desired to emphasize .the

fact that interpretation of the invention should only be, Conclusive wh n maderinpthe,

Iclaimflz tion'and' an opening inithjetop of'the'ring'i' connecting with said apertnre -a sliding breechlblock, means for opening andfclosing the'block, a tray pivoted to a lower edge v V of the "block and adapted to formarest ifor the round-when theqblock i isfopen,

means whereby the; tray is folded agamst the block as theblock is-elosed; alatch having a'short-rib anda recess mounted in the so ring at the head of the openin' andrnormally moved'intothe p'athof t e blockto;

prevent its-closing, said latchTadaptedto be manually'lifted bythe loader inwithdrawing I a his hand after inserting a. round,.za"springi pressed. catch adapted to enter the .recessin:-

athe-latch 'when 'th'efllatch" is inthe raised V position' and to engage the v rib. when latch is in the loweredjpositionaand 'ade pending lug on 1 the catch'L-adaptd -to be V struck .by thebl'ockin closing-towithdraw the catch from the recess in thelatch. F

.2. Agun, abreech ring 1ther eon',-havi'ng1anaperture for inserting a round iofainmunition andan openingji'n the top' 'o f the f l 1' connecting" with' said V aperture, a; sliding breech block, meansifor opening and closing;v the. block, a latchihaving arshort'riband a.

recessinounted in the'ring atthe headof the opening and normally 'nioved intothe] 'athi; 00

of'the block tolp'revent'its' closing,said atch adapted to be manually'lifted b'ytheloader in Withdrawing his hand after inserting a" 5 round, a s'p'ringiipressedcatch fadaptedtof enter the recess in the -latch when the latch 1 is in'the rais'ed'positionj and :to engage-therib-'when-the latch is in'thelowered posi- Thebreech. mechanism includes a' more f tion,' and 41 d di g l on the i' adaptedv to be struck bythe blockin clot-sing Withdraw e' tch from the. recess in: thelateh; v I lip 'i 3. A gun, a breech ring thereon having j an aperture for inserting around Offammui: A nitionand an: opening in theto'p ofthef ing; 1 connecting with said aperture, a a sliding; 1

breech block; means foropening and closing the block, a latch mounted-in the ring'at thei both its lowered andrai'sedposition; and-a.

depending lug on the-'catch whereby the beoperated 'byf-the-hblock inf-c10 3 5 same may s 4.: A-guma breechring- .there0n having ja loading aperture and-an opening in thejtopr; of the ring. connecting with said apertureg a 1. 'A gun, a breech ring thereon havinglanjo [aperture for;1nsertinga round of ammuni i 10 of the sliding breech block, a latch mounted in the ring at the head of the opening and normally moved into the path of the breech block to prevent its closing, said latch 5 adapted to be manually raised to clear the block, and means releasable by the block for holding the latch in the raised position.

5. A gun,'a breech ring thereon having a loading aperture and anopening in the top ring connecting with said aperture, a sliding breech block, a latch mounted in the ring and normally moved into the path of the breech block to prevent its closing, said whereby the tray is folded against the block as the block is closed.

GEORGE M. McCANN. 

